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Old 02-14-2011, 07:22 PM   #114 (permalink)
aerohead
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Quote:
Originally Posted by cfg83 View Post
Frank -

I did an overlay :



NOTE: My image may be incorrect if my choice for "apex/center of camber" is incorrect.

The (very) thin red line is the latest overlay we are looking at. The thicker green line is another overlay base on this image :



The 9.0 degrees is an interpretation of the red and green lines. The 12.7 degrees is the slope of the "shadow" over the EV-1. The EV-1 "shadow" is closer to a straight line from the apex, while the other slopes are more more curved (I hope that makes sense).

Base on the slopes I am seeing, I am going to split the difference and say that the "goal" should be an angle of close to 11 degrees (at least for the EV-1).

CarloSW2
I think the green original form needs to be shrunk down a smidgeon.We're working with the outer extremities of the image.
--------------------------------------------------------------------------
As far as the angles go,the intention is to locate the point of interest along the template,then ascertain the actual tangent angle at that point,splitting the point with a straightedge,then using protractor to find the angle.
The drawing I used is 30-inches in length.The closer you get to full scale,the higher the accuracy.
Some angles are given at each 10 % aft-body increment.
-------------------------------------------------------------------------- And remember,the EV-1 is 'dirty' in back.It suffers flow separation at 22-degrees.
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